Question 7.43: A refrigerator used for cooling food in a grocery store is t......

The cooling effect and the COP of a refrigerator are given. The power input to the refrigerator is to be determined.

Assumptions The refrigerator operates steadily.

Analysis Rearranging the definition of the refrigerator coefficient of performance and applying the result to this refrigerator gives

\dot{W}_{\text {net,in }}=\frac{\dot{Q}_{L}}{\mathrm{COP}_{\mathrm{R}}}=\frac{10,000 \mathrm{~kJ} / \mathrm{h}}{1.35}\left(\frac{1 \mathrm{~h}}{3600 \mathrm{~s}}\right)=\mathrm{2 . 0 6} \mathrm{k W}